@get:Inject
    abstract val execOperations: ExecOperations

    private
    val suspiciousDaemons = ConcurrentHashMap<String, MutableSet<String>>()

    private
    val daemonPids = ConcurrentHashMap.newKeySet<String>()

    private
    val logger = Logging.getLogger(DaemonTracker::class.java)

    override fun close() {
        logger.lifecycle("Cleaning up daemons...")
        cleanUpDaemons()
    }

    return Sets.newHashSetWithExpectedSize(expectedSize);
  }

  /** Returns the platform preferred implementation of a thread-safe hash set. */
  static <E> Set<E> newConcurrentHashSet() {
    return ConcurrentHashMap.newKeySet();
  }

  /**
   * Returns the platform preferred implementation of an insertion ordered set based on a hash
   * table.
   */